“I said if you don’t get off him and let him breathe, he will die,” Newcastle City Chief Inspector Peter Mahon told a committal hearing into Mr Slater-Dickson’s cause of death in Newcastle Local Court on Monday. 

Mr Batterham was lying on top of Mr Slater-Dickson, his left arm around his neck and his right arm raining down blows into the back of his head, in the driveway of a home in Cleary Street, Hamilton, about 400 metres from where he found Mr Slater-Dickson breaking into his house. 

Mr Mahon said Mr Batterham, now 35, seemed to loosen his grip on Mr Slater-Dickson and Mr Mahon put Mr Slater-Dickson on his left side, “in the recovery position”, because he was struggling to breathe.

Then, Mr Mahon said, something happened that inflamed the situation and made Mr Batterham respond even more aggressively than when he had first caught up to the man he found inside his home.

“Then Ricky bit Batterham on the hand,” Mr Mahon said.

“With that Batterham has responded by punching him and being more aggressive. 

“Again he has grabbed him around the neck and punched him. 

“Ricky’s arm was right up his back… his neck was really screwed around, twisted to the right and he was really struggling with breathing at this stage. 

“His neck was twisted further now than before. 

“He was aggressively punching him with his right fist. It was real violent, because he had been bitten.”

The committal hearing examining Mr Slater-Dickson’s cause of death will also hear from defence and prosecution medical experts. 

Mr Mahon said he could see the situation was escalating and he could not, no matter how hard he tried, get Mr Batterham off Mr Slater-Dickson, so he ran across the road and radioed police in a bid to communicate how dire the situation was.

He returned a few minutes later to find Mr Batterham was still lying on top of Mr Slater-Dickson, who was no longer struggling as much.

He tried again to drag Mr Batterham off. 

“I wasn’t mucking around,” Mr Mahon said. “I was trying my best to get him off him. “I just knew things were going pear-shaped.”

Moments later, a police vehicle roared into the street and Mr Batterham released his grip.

The police officers handcuffed Mr Slater-Dickson, who was still face down on the road, from behind and an aggressive Mr Batterham tried again to get to him, Mr Mahon said.

Mr Mahon pushed Mr Batterham in the chest and walked him down the road towards his house.

But when he returned to the scene he said he discovered Mr Slater-Dickson was still motionless and unresponsive. He told police to take his handcuffs off and tried to rouse him before paramedics arrived and commenced CPR. 

Mr Slater-Dickson’s cause of death will be the key issue at Mr Batterham’s murder trial, with prosecution and defence experts split as to the extent that violence played in him suffering three episodes of cardiac arrest and ultimately dying in hospital the day after the break-in. 

Mr Slater-Dickson had a “toxic” and “potentially lethal” level of methylamphetamine in his system that may have contributed to his death, Newcastle Local Court has previously heard. 

But medical experts have also raised a number of other possible factors that could have contributed to the death of the 34-year-old, including strangulation or asphyxiation from a “choke-hold”, blows to the head and a pre-existing cardiac disease. 

Mr Mahon was the only person to give evidence on Monday during what is expected to be a four-day committal hearing. 

Between September 10 and 12, Magistrate David Price will hear from both the defence and prosecution expert cardiologists, forensic pathologists and toxicologists. 

The defence claim that Mr Batterham should not be committed for trial for murder, citing their medical reports that indicate either the methylamphetamine in Mr Slater-Dickson’s system or other circumstances, independent of the assault, caused his death.

Mr Batterham remains on Supreme Court bail after twice being refused bail since being charged with Mr Slater-Dickson’s murder.

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